“Friends and associates said few U.S. citizens are closer to [Russian President Vladimir] Putin than Mr. Tillerson, who has known Mr. Putin since he represented Exxon’s interests in Russia during the regime of Boris Yeltsin.

“He has had more interactive time with Vladimir Putin than probably any other American with the exception of Henry Kissinger,” said John Hamre, a former deputy defense secretary during the Clinton administration and president of the Center for Strategic and International Studies, a Washington think tank where Mr. Tillerson is a board member.

In 2011, Mr. Tillerson struck a deal giving Exxon access to prized Arctic resources in Russia as well as allowing Russia’s state oil company, OAO Rosneft, to invest in Exxon concessions all over the world. The following year, the Kremlin bestowed the country’s Order of Friendship decoration on Mr. Tillerson.”